Social Security defines light work as being able to lift 20 pounds and 10 pounds frequently. In order to perform light work you have to be able to stand and walk for six hours out of an eight hour day. When SSA decides that you can do light work this means SSA has determined that you have the residual functional capacity (RFC) for light work. Residual Functional Capacity(RFC) is the most you can do despite your limitations. If you are limited to light work and you are over age 55 and none of your past work this finding is helpful to you.